1. Field of the Invention
The present invention relates to a symbol data read apparatus for reading symbol data such as bar-codes or the like and for outputting processed data.
2. Description of the Related Art
In general, a one-dimensional bar-code consisting of a plurality of bars and spaces alternately disposed is used as symbol data representing various information. A bar-code is normally printed directly on an article, or indirectly on a seal sheet or the like which is stuck on an article.
Japanese Patent Application KOKAI Publication No. 5-307627 discloses a bar-code read apparatus having functions of printing a one-dimensional bar-code as explained above, confirmation and reading thereof.
Further, when the presence of a bar-code need be kept secret from third persons, or when distribution control is needed although it is not desirable to print a bar-code on a product due to design matters, conventional methods of visible printing are not suitable. In view of such cases, Japanese Patent Application KOKAI Publication No. 3-154187 proposes a bar-code printing method of printing a bar-code with use of invisible material, e.g., photoluminescence ink which cannot be observed with eyes under normal light (including sun light). To read an invisible bar-code thus printed, light of a certain frequency having a particular wavelength (e.g., a near infrared ray) is irradiated, and radiation light having another wavelength is reflected therefrom, which is read out.
However, the one-dimensional bar-code data read apparatus described in the Japanese Patent Application KOKAI Publication No. 5-307627 deals with only one-dimensional bar-codes, and cannot read respective rows of two-dimensional bar-codes (or stacked bar-codes). A two-dimensional bar-code is constituted by a number of codes and therefore requires more data than normally required, e.g., confirmation data, so that a large amount of data must be subjected to processing. As a result of this, much time is required to read a two-dimensional bar-code, while there has not been a confirmation apparatus capable of processing such a large amount of data.
Meanwhile, a bar-code printed with ink of invisible material according to the Japanese Patent Application KOKAI Publication No. 3-154187 cannot be viewed with eyes, so that it is difficult to find degradation induced by heat and light such as sun light. Such deterioration causes reading errors. Degradation caused during use, such as stains of a label, chipping on its surface, or the like also causes reading errors.
Therefore, a user finds it impossible to properly read a bar-code before a reading error is notified after an operation for reading the bar-code is once performed. In a case where a bar-code printed on a card or the like cannot be read out, the card is determined as a card error. If a new card is not reissued immediately after a card error is found out, the card cannot be used until reissue of a new card. This has been a problem when a card is managed.